OMAP3: PM: Do not rely on ROM code to restore CM_AUTOIDLE_PLL.AUTO_PERIPH_DPLL

[pandora-kernel.git] / arch / arm / mach-omap2 / cm2xxx_3xxx.c

diff --git a/arch/arm/mach-omap2/cm2xxx_3xxx.c b/arch/arm/mach-omap2/cm2xxx_3xxx.c
index 9d0dec8..38830d8 100644 (file)
--- a/arch/arm/mach-omap2/cm2xxx_3xxx.c
+++ b/arch/arm/mach-omap2/cm2xxx_3xxx.c
@@ -247,6 +247,7 @@ struct omap3_cm_regs {
        u32 per_cm_clksel;
        u32 emu_cm_clksel;
        u32 emu_cm_clkstctrl;
+       u32 pll_cm_autoidle;
        u32 pll_cm_autoidle2;
        u32 pll_cm_clksel4;
        u32 pll_cm_clksel5;
@@ -319,6 +320,15 @@ void omap3_cm_save_context(void)
                omap2_cm_read_mod_reg(OMAP3430_EMU_MOD, CM_CLKSEL1);
        cm_context.emu_cm_clkstctrl =
                omap2_cm_read_mod_reg(OMAP3430_EMU_MOD, OMAP2_CM_CLKSTCTRL);
+       /*
+        * As per erratum i671, ROM code does not respect the PER DPLL
+        * programming scheme if CM_AUTOIDLE_PLL.AUTO_PERIPH_DPLL == 1.
+        * In this case, even though this register has been saved in
+        * scratchpad contents, we need to restore AUTO_PERIPH_DPLL
+        * by ourselves. So, we need to save it anyway.
+        */
+       cm_context.pll_cm_autoidle =
+               omap2_cm_read_mod_reg(PLL_MOD, CM_AUTOIDLE);
        cm_context.pll_cm_autoidle2 =
                omap2_cm_read_mod_reg(PLL_MOD, CM_AUTOIDLE2);
        cm_context.pll_cm_clksel4 =
@@ -441,6 +451,13 @@ void omap3_cm_restore_context(void)
                               CM_CLKSEL1);
        omap2_cm_write_mod_reg(cm_context.emu_cm_clkstctrl, OMAP3430_EMU_MOD,
                               OMAP2_CM_CLKSTCTRL);
+       /*
+        * As per erratum i671, ROM code does not respect the PER DPLL
+        * programming scheme if CM_AUTOIDLE_PLL.AUTO_PERIPH_DPLL == 1.
+        * In this case, we need to restore AUTO_PERIPH_DPLL by ourselves.
+        */
+       omap2_cm_write_mod_reg(cm_context.pll_cm_autoidle, PLL_MOD,
+                              CM_AUTOIDLE);
        omap2_cm_write_mod_reg(cm_context.pll_cm_autoidle2, PLL_MOD,
                               CM_AUTOIDLE2);
        omap2_cm_write_mod_reg(cm_context.pll_cm_clksel4, PLL_MOD,